Re: WHERE col = ANY($1) extended to 2 or more columns?

On Thu, Feb 9, 2023 at 9:28 AM Alban Hertroys <haramrae@gmail.com> wrote:

>
> > On 9 Feb 2023, at 16:41, Dominique Devienne <ddevienne@gmail.com> wrote:
> >
> > Hi. We are implementing an API which takes a list of row keys, and must
> return info about those rows. To implement that efficiently, in as few
> round-trips as possible, we bind a (binary) array of keys (ints, uuids, or
> strings) and that works great, but only if the key is a scalar one.
> >
> > Now we'd like to do the same for composite keys, and I don't know how to
> do that.
> > Is it possible? Could someone please help out or demo such a thing?
> > We are doing it in C++ using libpq, but a pure SQL or PL/pgSQL demo
> would still help (I think).
>
> This works:
>
> => select (1, 'one'::text) in ((1, 'two'::text), (2, 'one'::text), (1,
> 'one'::text), (2, 'two'::text));
>  ?column?
> ----------
>  t
> (1 row)
>
>
But you cannot write the right-side of the IN as a single parameter which
seems to be the primary constraint trying to be conformed to.

David J.